Quote:
Originally Posted by Qtx
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Am I not supposed to be blocked?
Anyhow, anything from 1 to several dozen properties share one coax cable going to the street cabinet.
A few to several dozen of these are combined into one larger cable going to a fibre cabinet (sometimes going through other coax cabinets in between).
The fibre cabinet combines up to a few dozen of the coax lines from smaller cabinets into a fibre-optic link to the CMTS. Each of these "links" is essentially a separate service node.
Multiple service nodes can be run over one optical fibre (WDM) or they can each get a separate physical fibre.
The fibre nodes then connect into the CMTS (not neccessarily directly). Each node is served by one or more line cards.
So, you get a few dozen to a hundred customers sharing one cab. Several cabs, totalling maybe 500-1000 customers being one fibre "node". Several fibre nodes may be carried over one fibre-optic cable, totaling thousands more.
The numbers I've seen in the past show VM serving ~100-500 customers from one line card. The actual numbers vary greatly area, network layout, and the number of node splits VM feel like doing. Several line cards may serve one node or several nodes may be served by one line card. The line cards are not really the bottleneck, the size of the nodes are.
The equivalent infrastructure on BT is each customer gets a dedicated cable all the way to the fibre cabinet. The fibre cabinet has a minimum of one fibre per ~60 customers to the exchange.
On ADSL each customer gets a dedicated cable all the way to the exchange.